Founded in California by people who previously worked at Paypal and Yahoo, LinkedIn is now available in 20 different languages.

Twitter was founded in 2006 by Jack Dorsey and three others. Dorsey is still at the company as chairman.

Yahoo was originally just a list of URLs. It used to employ Google as a search engine before developing its own technology. In 2013, it surpassed Google for the first time in US traffic. But Google eventually took the lead back.